A gun cartridge
developed by Springfield Armory
for the M1903 bolt action rifle
The cartridge carries a 7.62 millimetres (0.30 inches) bullet in a 63 mm long case.
With the adoption of the M1903 rifle, a new cartridge was also adopted. The cartridge designed for the rifle featured a rimless bottlenecked case, and a round nosed 220 grain bullet, advertised at 2,300 feet per second muzzle velocity.
In 1906 (hence the -06 -- a cartridge carrying a .30 inch bullet adopted by the army in 1906), the United States adopted a lighter spitzer bullet of 150 grains and a muzzle velocity of 2,700 feet per second. The maximum range for the new cartridge, now designated the M1906, was found to be between 3,300 and 3,400 yards, with the muzzle of the rifle at an angle between 29 and 45 degrees.
The .30-06 is well suited for larger game like elk / moose and even bear.